Sheave and pressure rider



Aug- 10, 1943. Y J. c. PATTERSON, .JR 2,326,671

SHEAVE AND PRESSURE RIDER Filed Feb. 4, 1943 gnam/vbo@ Patented Aug. 1o,1943 UNE-reo {Lgt-STAT es Per 2,32a67i1: I

particularly it has reference g-to such Combination wherein the sheaveis driven and is of av novel structure adapte-d -to grip the cablethroughout Q asubstantial proportion offthe surface thereof.

`applicationis a continuation-impart of application lSerial Number407,811,-led August 21.11941,A Y y I sheaves of'the present type,although of Wide adaptability to any number ofhosting problems, areofparticular utility in'coniunction With-the paying outY device on theoutboard end of .the

boom. of a crane employed for handling shipbornc' aircraftand the like;vlnhoisting'aircraft aboard ships, it is customary-to use a'hoist havinga paying outndevice acting upon and serving tov drive the hoist cable sothatV the use .of a weight in the` hoistingwhip may be avoided, Vthelatter being a dangerous expedient-because ofthe factthat the cablesuspende-d weight may swing to and froA and in so doing damage theplaneor injure ioe occupant thereof duringthe illtial'hook-on ieriod. Apaying out 'device of the'type inques tion is disclosed in my Patent No.Y2,942,431,'issued June 2, 193e.l l Y l aIn the'employment ofsheavesfiori-paying out cablel inthe manner outlined above, it is,.,.ofcourse, necessaryto provide somesuitable means for Ydriving the sheaveand for imparting-the iff movement thereof to zthe cablesvvithoutslippage.

Y Itis the usual practice to. insure sufilcient-d-riving frictionbetween cable, andY sheave by vapplying pressurethrough a rollerdisposed to make tangential contact with the loable Vapr beingzaetedpressures, ,but also structed` and .--arrangednection paying out-sheavesvof thetypeh-ere-V tofore known yis lack ofadaptability iorruse withcables of differingV diameters and consequently l inability.v ,tocompensate for Wear 1of., either", Athe sheave groove ,or` thecable. Theresult of; the J foregoing is, ofcourse, frequent Aandcostlyre-kplacements., 1 f

It i'stherefor'e,an objectfof this invention4 to provide-fa paying outdevice-in which 'adequate driving -friction between` cable and sheave ismaintained at an optimumvalue while damage to and vvearl of-ibothcable'eand sheavefis minimized.

.The present inventionA :contemplates aY driving sheave and` cooperatingYpressure roller so con-r i 1 that satisfactory paying? out is achievedv.vvitlrtheuse ofjmoderate pres# sures. The invention` furthercontemplates :the

f provision cfa sheave of'sucn construction that`` the essential.element in achieving the said lresult is formed of asubstance which notonlyy is peculiarly adapted rfor-,permitting reducedvoperation A,

provides a cable contacting surface ,ofV high' Wearfresistant quality. E

on by a force tending to urgeit -radi-allytow'ard' the axis of thesheave. ,The required pressures inthe case of sheaves oflnovvnconstruction are rather high land `consecuiently result in severesqueezing action on the cable tending to forceout,v

Concornitant to the :advantages i set out .y above is a wideadaptabilityt'o operation with cables of v a. Size varying ,withrespect, tothe riding surface ofthesheave, l A

Otherfobjects andv advent ages of the` invention will be apparent from aconsideration ofthe'follovvingj detailed-descriptiongin conjunctionVwith thefannexeddravvingvvhereins Figure 1 is-aviewshowingtht-Srelationship`ofr -Y I ,pressure rider accordingdrive sheaves, cableand to the 1 present Ainvention vFigi-irez is .a-partial,sectiontalrenalonggthe y y line 2v2 ofV Figure 1; and.V

Figure 3 isa partial plan viewishoiving a rriodi'v f fcationvvhereinthecableeca'rrying surface of the the lubricating and corrosioninhibtingcomposition with which theV hemp core thereof isy customarilysaturatede- Both` the lossof lubricant and the .intense pressurecontributeto excessive Wear on both cableandrsheave; Then too, Ethe highpressure used Yhas also been a source of lf- .i

culty in automaticr tension hoists, the powerjrequired for merelypulling thezcable through vthe Ingen attempt sheaves being of ahi'griforderiV to avoid, at least in part, these dilfcultes; thepressure .rider has beenheretofore'- mounted in a complicated manner torelease the :cable at' all times when the deviceisnot'actuallypayinggvout sheaveis provided With'a tread'. f

In .general, the'f-invention contemplates the combination ofagdriver'sheav'e and pressure rider wherein thev sheave is constructedwith-a resilient body orspool mounted in position/by rigid ndern#l bersbut `adapted to be deformed vin a novel man-f ner in its peripheralportion. The periphery of the resilient'bodyzis formedwlth a'circumferene 'tial groove for Carrvinethecable.; 'rhezprovistcnfordeforrnation ofthe resilient spool is such that the sides4 ofi-thel.groove[will be'forced inwardly to; bear against a`substantial],proportion of fthe 1 surface of the:oableiupon'pressurebeing applied -to the cable through theinediumof the pressure yV.17ol1er.,.- j-

1-Referring-specically yto Figuresyljand; a

A55 cable I0 'is-carried betweena sheave H and a pressure roller I2,provided'with a suitable means Y for application of pressure, such asthe hydraulic cylinder I3, illustrated in Figures 1 `and 2. The

sheave II comprises rigid flanges I4 and a re` silient body portion I5of a synthetic rubber ma' terlal maintained in place. between the'angesYby a plurality of clamping bolts I6. The flanges are mounted on a shaftI`I by vconventional means and the shaft I'I is provided with suitabledriving means, not shown. Resilient body portion I5 isfin the form of anannulus, as may be seenin Figure 2, and is provided with a peripheralgroove I8 for the reception of cable ID. The e flanges I4 are of lesserradius than the body por- A tion I5 and the circumferential edges ofthelat'- ter which extend beyond the flanges are beveled .atISL In additionto pressure yroller IZ'hydraulic cyl- *Y lnder I3 actua'tes a pair ofpressure-riders 2l]VY having beveled faces complementa-ry to the bev'-eled edges I9 of theresilient body I5.,"' To this end, pressure ,ridersand roller I2 are mounted ona common shaft' 2I` pivotally mounted at itsends. inl-a yoke 22; Yoke 22'is connected tothe extensible portion 23'of. hydraulic cylinder lvI3.v

' In Figure 2 it Will be noted-that the'diameter sist in adjusting boththe size of groove I8 and v the side pressure exerted upon the resilientbody portion.

vcarrying'groove of the resilient body' I5. Figure 3 illustrates'aresilientl body I5 having radial slots v24 extending from the surface ofthe groove I8 a substantial distance into the body I5. Preferably thedepth of the slots 24 is substantially equal to the depth to which thegroove I8 will be worn before replacement is advisable.

It will be apparent to those skilled in the art that variousmodifications and adaptations of l5 my invention may be made withoutdeparting Yfrom the spirit thereof. For example, it is often advisabletoincorpcrate friction enhancing ma- -serials such as metal wire, fibre,hemp, carbon,

. and other substances having suitable properties of riders 20 isgreater than the diameteofjroller Y I2.' Thus, when hydraulic CylinderYI 3 'is-actuated, shaft 2I is moved toward shaft II and roller I2A movesthe cable radially inwardly tendingtc cause' the resilientmaterial tovsurround it, which tendency is augmented by 'the lateral force 're`solved from the radial --rnovement of riders 2l) acting on vtherespective. beveled portions VI9 Vof bodyportion I5. This being thecase., the frictional force acting on the Vcable v'is Vvcon'.'si'derablygreater than it would bel if roller YIz'were urged under vthe' samepressure and "the'c'orrta'cty area were not augmentedv bydeforrhation ofthe 'body portion. ofthe sheave. j

' By means of the device' discussed abovejit is found that wearon'the'cable is greatly reduced by the coactionfof two'fa'ctors.'VBecause of the adjustable gripping action Ofpdrivinglcont'actbetween'sheave a'nd cableeitiis'possible to use drasticallylreducedpressures. Further', the .wear Ydue to friction Vbetween the surface ofa metal and-a resilient substancefis much less than the' Wear duetoffrictio'n at'a metal-to-'rnetal contact. Y Al-1 though `I"m'a'y userubber or Vany other resilientk substance, I prefer to'usethe so-called#synthetic" substances because of'tlieir greater 'resistance'todeterioration' in the presence'of oilssuch as are used for lubricationand corrosion inhibition of the cable.' Such Syntheticcompositions i asNeoprene, Thiokol .'Foririicaf` and'the like are found to be eminentlysatisfactory. I have also found that the'use of the presentl de viceresults in longer lif'e of the cable because the tendency to squeeze outthe oils used for lubrica-'f tionvand corrosion'inhibition is greatlyreduced. vBy theuse of a resilientbody I5 :disposed be#` tween rigidflanges' I4 which may be drawn to-v gether by bolts I6 it. isevidentthat'ithe initialY diarnerterlof groove -I8fcan` be adjusted toreceive cables of-.different cross sectional areas. Fur' inthe resilientbody I5. It is to be understood that "the invention is not limited tothe specific forms illustrated and discussed, butis limited only by thescope of the' appended claims.

WhatI claim is: i p 1.*In the combination of aV sheave *havingaperipheral groove ltovreceive a cable, a'riderco'- operating withsaidgroove and pressure means to apply pressure to said rider substantiallyradi'- ally of said sheave; a sheave `comprising a resilient bodyportion in which: the groove is formed, the y peripheralfedges of saidbody portionV being beveled,` a pair' of riders having beveledfacesadapted to cooperate with'the beveled edges of said body portion" and'compress the periphery thereof longitudinally, and `means to Yapplypres;

sure t'ofsaidlast-named riders. `2. In the combinationY of a sheavehaving a peripheral 'grooveto'receive a cable, a vrider cooperating withsaid groove and pressure'means to apply pressure to said ridersubstantiaillyvradially of said sheave; a sheave comprising a resilientbody' portion in which the groove is formed, the peripheral edges ofsaid body portion being bev` eled, a pair of riders having beveled facesadapt-f ed to `cooperate with the-beveled edges'` of said body portionand compress the periphery thereof longitudinally, and means connectingsaid lastca'ble'"gripiiiirig'V qualities.

named yriders to the pressure means to be operat-` ed thereby, wherebyupon'operationof saidfpr'es-J sure means all of the riders areactuated-'simultaneously'. l

3. A device as defined in'V claimwl'vwherein saidV resilient'bodyportion is providedwith a plurality of Vradialslots extending'inivardly'rfrorn the bottom ofthe Aperipheral'groove Vto affordimproved' lfrA device as denedin claim wherein'said resilient bodyportion] is provided with a pluralityy l tolf radial slots extendinginwardly from the botthermore; the size .of the Vgroovernay be'alteredYVto compensate forV wear' by lmerely drawing i flanges I4 together. This"adjustment therefore renders installation less diflc'ult andreplacementless frequent. Alongv these'same lines, it may be desirable tomakealthreaded connection between ridersk ,Z and shaft 2l so that theformer may-be moved toward and away fromfoneanother to astom of theperipheral groove to afford improved cable gripping qualities. w Y 'YV5. Alvdevice as defined in clairnl 1 further 'corn-f prising,"means fordrawing said flanges toward one'another to reduce the diameter oftheperipheral'groove, whereby to render the sheave adaptable 'to use'withcables of different" diameters and to allow compensationffor wear.

l 6. A device as deflned'in claim 2 furthercomlprising, means fordrawing said flangestoward oneanother to render'the diameter of the pe.-

fripheral'groove, whereby to'render" the sheave adaptable to use withcables` of different diam@- etersand to'fallowcompensation for wear.Y l'K JOSEPH Cf PATTERSON. fJR;

